Bluebirds can readily use our help for housing.  Bluebirds cannot excavate their own houses, buy rely on old woodpecker holes or rotting trees for their homes.  A manmade house is a welcome sight to most bluebirds, however, they tend to be a little more picky than most birds about how their house is designed and where it is located. 

The entrance hold should be about 6 to 10" above the floor and the diameter of the entrance hole should be 1.5".  Be sure the box has ventilation holes in the top and drainage holes in the bottom.  Another good feature is an easy open side to check on the progress of the nesting birds without disturbing them.

Bluebird boxes can be mounted on poles, fence posts, utility poles or trees.  Posts or poles are the best for providing protection from predators.  Mounting on trees is the least desirable.  Ideally, the nest box should be mounted 4 to 5 feet above ground, there is no single compass direction that the bluebirds prefer, but try to face them away from prevailing winds.  The most important aspect of mounting is to face the box toward some tree or shrub within 100 feet.  When the young leave the nest they will make an initial flight to safety.

To keep sparrows out, pair boxes 5-15 feet apart.  The sparrows will only nest in one, leaving the other open for bluebirds.